1. Field of the Invention
The invention relates to a battery power management. Particularly, the invention relates to a battery power management system and method.
2. Description of Related Art
To facilitate user's carry and usage, a portable electronic device (for example, a notebook computer) is generally assembled with a battery set. In this way, an operating power of the portable electronic device can be provided by an external power adapter or the assembled battery set.
FIG. 1 is a block schematic diagram of an existing battery power management system. Referring to FIG. 1, the battery power management system 100 includes a battery set 110, a battery measurement chip 120, a battery protection chip 130, resistors R11-R12 and a capacitor C1. The battery power management system 100 is connected to the external power adapter (not shown) through power terminals TM11 and TM12. The battery measurement chip 120 measures an electric quantity of the battery set 110 through a node between the resistor R11 and the capacitor C1, and provides a primary protection mechanism for the battery set 110. The battery protection chip 130 is used for providing a secondary protection mechanism for the battery set 110. In this way, the battery power management system 100 can both measure the electric quantity and maintain security of the battery set 110.
Since the battery measurement chip 120 is configured at a front end of the system, a high voltage transmitted by the power terminal TM11 is first transmitted to the battery measurement chip 120, and then the high voltage transmitted by the power terminal TM11 drops on the battery set 110 and the resistor R12 to form a low voltage for transmitting to the battery protection chip 130. When the system goes abnormal (for example, over voltage, over current, etc.), the battery measurement chip 120 is first damaged, and the battery power management system 100 cannot normally operate.
In an actual application, the battery set 110 can be a single-cell or a multi-cell battery, where each battery includes a plurality of battery cells. If the battery measurement chip 120 is implemented by using a low-voltage process technology, it cannot be used in a high-voltage application of the multi-cell battery system. Moreover, if the battery measurement chip 120 is implemented by a high-voltage process technology, a layout area of the battery power management system 100 and mass production cost thereof are increased.